/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.onami.factoryannotation;
  
  import java.lang.annotation.Annotation;
  import java.lang.reflect.Field;
  
  import org.apache.onami.factoryannotation.AccessibleHelper.AccessibleHelperCallback;
  
  import com.google.inject.MembersInjector;
  import com.google.inject.ProvisionException;
  
  class FactoryAnnotationSingleFieldMemberInjector<T, A extends Annotation>
      implements MembersInjector<T>
  {
  
      private final FactoryAnnotationProvider<T, A> factoryAnnotationProvider;
  
      private final Field field;
  
      private final A annotation;
  
      private final FactoryAnnotationProvision<T, A> factoryAnnotationProvision;
  
      private final FactoryAnnotationProvisionListener<T, A> provisionListener;
  
      FactoryAnnotationSingleFieldMemberInjector( final FactoryAnnotationProvider<T, A> factoryAnnotationProvider, final Field field,
                                         final FactoryAnnotationProvisionListener<T, A> provisionListener, final A annotation,
                                         final FactoryAnnotationProvision<T, A> factoryAnnotationProvision )
      {
  
          this.factoryAnnotationProvider = factoryAnnotationProvider;
          this.field = field;
          this.annotation = annotation;
          this.factoryAnnotationProvision = factoryAnnotationProvision;
          this.provisionListener = provisionListener;
      }
  
      public void injectMembers( final T instance )
      {
          AccessibleHelper.executePrivileged( field, new AccessibleHelperCallback<Field>()
          {
  
              public void execute( final Field accessibleObject )
              {
                  try
                  {
                      // If annotated with both @Inject and a binding
                      // annotation it is possible that there would be two
                      // injection request, so just prevent injecting a
                      // value a second time
                      if ( accessibleObject.get( instance ) == null )
                      {
                          final FactoryAnnotationProvision<T, A> ip = FactoryAnnotationProvisionImpl.modify( factoryAnnotationProvision, instance );
  
                          final T value = factoryAnnotationProvider.buildValue( annotation );
  
                          // Notify listener before we inject the value
                          if ( provisionListener != null )
                          {
                              provisionListener.beforeInjection( ip, annotation );
                          }
  
                          accessibleObject.set( instance, value );
  
                          // Notify listener after injection is done
                          if ( provisionListener != null )
                          {
                              provisionListener.afterInjection( ip, annotation, value );
                          }
                      }
  
                  }
                  catch ( final IllegalAccessException e )
                  {
                      throw new ProvisionException( "Provision failed", e );
                  }
              }
  
          } );
      }
  
      @SuppressWarnings( "unchecked" )
     static final <A extends Annotation, I, T> MembersInjector<I> buildMemberInjector( final FactoryAnnotationProvider<T, A> factoryAnnotationProvider,
                                                                                       final Field field,
                                                                                       final FactoryAnnotationProvisionListener<T, A> provisionListener,
                                                                                       final A annotation,
                                                                                       final FactoryAnnotationProvision<T, A> factoryAnnotationProvision )
     {
 
         return (MembersInjector<I>) new FactoryAnnotationSingleFieldMemberInjector<T, A>( factoryAnnotationProvider, field,
                                                                                  provisionListener, annotation,
                                                                                  factoryAnnotationProvision );
 
     }
 
 }